Agakoresho ko kugabanya umuvuduko ni valve igenzurwa igenzura uburyo umwuka winjira muri moteri. Iyo gazi yinjiye mu muyoboro w’amazi, izavangwa na lisansi maze ibe uruvange rushobora gushya, ruzashya rugakora. Ruhujwe na filter y’umwuka, moteri, izwi ku izina rya moteri y’imodoka.
Moteri za lisansi zo mu bwoko bwa "throttle four stroke" muri rusange zisa gutya. "Throttle" ni kimwe mu bice by'ingenzi bya sisitemu ya moteri y'imodoka ikoresha amashanyarazi muri iki gihe. Igice cyo hejuru cyayo ni akayunguruzo k'umwuka, igice cyo hasi ni silinda ya moteri, kandi ni umuhogo wa moteri y'imodoka. Kwihuta kw'imodoka kurahinduka, kandi "throttle" yanduye ifite isano ikomeye, gusukura "throttle" bishobora kugabanya ikoreshwa rya lisansi bishobora gutuma moteri ikoroha kandi ikomeye. "throttle" ntigomba gukurwaho kugira ngo isukure, ahubwo ba nyirayo bagomba kuganira byinshi.
